Earth anchor



J. BLACKBURN.

EARTH ANCHOR.

APPLICATION FILED MAR. 18, I918.

Patented Feb. 28, 1922.

//v Vin 70R UNITED S A S PATENT OFFICE JASPER BLACKBURN, or WEBSTER GROVES, MIssoum.

EARTH ANCHOR.

T0 aZZ'w/wm it may concern:

Be it known that I, J BLACKBURN, a citizen of he United States, and res1dent of Webster Groves, St. Louis County, Missouri, have invented certain new and useful Improvements in Earth Anchors, oft

which the following isa specification con-' taining a full, clear, and exact description, reference being had to the. accompanying drawing, forming a part hereof.

Hy invention relates to improvements in earth anchors, especially of the expanding type having fiukes or plates for extension into the earth beyond the hole formed to receive the anchor.

My improvements consist inthe novel con struction, arrangement and combination 01"- parts, as will be fully, clearly and concisely set forth, definitely pointed out in my claims and illustrated by the accompanying drawing in which Fig. 1 is a plan of an anchor, embodying my improvements, showing the anchor rod in section. v

Fig. 2 is a view similar to Fig. 1, showing the anchor somewhat expanded.

Fig. 3 is a sectional elevation taken on the line 3 -301 Fig. 1.

Fig. 4; is an end elevation of one of the flukes.

Fig. 5 is a detail sectional elevation, taken on the line 55 of Fig. 3, showinga fluke guide, and

Fig. 6 is an elevation, on a reduced scale, showing the anchor, with its rod attached, as placed at the bottom of a hole, and a tamping bar in position to affect anchor expansion by impacting the inclined planes or wedges carried by the flukes.

Referring to the drawings by numerals, 7 designates the crown, baseplate or body portion of the anchor, which is of circular plate formation and its uppermost face plane, and upon which the fiukes or expansion plates 8 are superposed and supported.

Centrally through the crown there is formed a hole 9, through which the anchor Specification of Letters Patent. Patented F b 2 1922 v V V i v Application filed March 18, 1918. Serial No. 223,089.

rod, 110, may be extended and which rod, as 15100111111011.3 18 arranged for connectionwith a cable (not shown) for the anchorage of a pole or the like.

' In my drawing, I show .a three-way anchor, that is, one having three flukes or expansion plates, but in no sense wish to be understood as limiting myself tothis num ber of flukes, as obviously, the number may are, sectionally, of T-shape, and further, by

preference the crown is provided with guards 14L, integral with the lower face of the crown, and projecting therebelow, having their outermost'end's open to receivethe guide ribs 12, and their interiors sectionally shaped to conform with the guide ribs.

One function of the guards is to form an enclosure for the guide ribs of the flukes, so that when thefiukes are moved, as in their lateral expansion movements, the guide ribs may move in unobstructed paths, that is, within said guards, instead of being sub jected to engagement with the bottom of the anchor-hole or loose earth or other matter resting on the bottom o'f'the'hole.

Another function of the guards is that they augment the slots, 11, in their tendencies to hold the flukes to straight line movements during expansion.

As shown best in Fig. 2 (by dotted lines,) the guards are integrally connected with each other at their innermost ends, and surrounding the hole 9, (as shown in Fig. 3) are formed solid as at 15. By this construc tion, I provide a relatively great body surrounding the hole 9 in the crown, against which the nut 16, on the'anchor-rod seats, and at which point in the crown is received the strains incident to tensions on the anchor rod.

A distinct advantage arising out of the detail structure just recited is that I am enabled to form the crown-proper out of a minimum of material, that is as to thickness,

relying upon the body 15, to prevent breakage or buckling directly at the point of applied strains and the spider effect produced by the guards to stiffen the crown generally. In some cases, I may further stiffen the crown, as shown in Fi 3, by a number of arcuated ribs, such as 11, extending between the guards and projected downwardly,

In installing anchors of this type it is customary to insert the anchor rod through the crown and secure it to the crown by a means such as the nut 16, referred to, prior to dropping the anchor into the hole, hence in order to provide for the recovery of the anchor rod, if desired, and after complete .installation I form on the lower face of the solid body 15 the walls 18, which engage the nut to hold it against rotation and thereby am enabled to rotate the anchor rod to effect its release from the nut, after which the rod may be drawn from the ground and again utilized. p

--As shown best in Fig' 2 each of the fiukes 8, in a three-way anchor, comprises a flat,

plane faced body 19, arranged to rest upon.

the upper plane face of the crown'l', and an integral fiat, plane faced extension 20, occupying a plane above the body 19, whereby it may overlap the body 19 of the next'adjacent fluke. The dividing linesbetween the bodies 19 and extensions 20 showingv as bevelled steps 21. I

The fiukes each have an outer margin 22, bevelled or sharpened so that it may be readily forced into the earth, which is an arc of a circle of the same radius as the margin of the crown and as shown in Fig. 1,

the three flukes, when close-d rest-upon the crown wholly within 1ts compass.

- The chord or inner margin 23, of each fluke extends substantially diametrically of the crown and by preference, merely to economize in material, is provided with reentrants or concavities 24.

Upstanding from the upper face of each fluke is a wedge or inclined plane 25, leading upwardly and from the chord or inner fluke margin toward the outer curved fluke margin, and by preference this wedge occupies a position directly over and parallel with the guide rib 12.

The operation of expanding my improved anchor will be'readily understood by reference to Fig. 6 wherein the anchor is shown at the bottom of a hole with its anchor rod secured thereto and an impacting device disposed over one of the wedges. It will be obvious from this showing that blows delivered upon the wedge will cause the fluke to be forced or driven laterally to effect an anchorage in the solid earth surrounding the hole.

The impacting device'referred to may be the tamping tool employed in the replacement of the removed earth from the hole, thereby making it possible to install such anchors, with only a tool for forming the hole such as an earth auger and the tamping tool, 7

I claim: 7 1. In an earth anchor of the class described, crown, a rod connected with the crown, a plurality of superposed flukes supported by the crown and arranged for radial, lateral movements thereover, and a de-.

vice, having an upper surface inclining downwardly and inwardly toward the center of the anchor, carried by each fluke to provide for the movements of the flukes by impacts delivered directly to said devices.

2..In an earth anchor, a crown, of substantially disc shape, a plurality of substantially flatflukes supported by the crown, an element having an upper surface inclining downwardly and inwardly toward the center of the anchor formed integral with each fluke, means for guiding the fiukes in straight line movements'over said crown and guards for said guidlng means.

JASPER BLACKBURN. 

